1. Field of the Invention
The present invention relates to a mechanical cottonseed delinting device in which it is desired to delint cotton from the cottonseeds without damaging the cottonseeds so as to permit the seeds to be planted. In order to effectively delint such cottonseeds, the machine utilizes a series of cages in which the cottonseeds are trapped between a brush and a screen mesh enclosure so as to be subjected to a series of brushing treatments. The brushing treatments are effective in removing the cotton lint from the cottonseed.
2. Description of the Related Art
The most common methods used today for delinting cottonseed all relate to the use of various chemical processes. The earliest chemical process was to saturate the cottonseed with concentrated sulfuric acid. The short cotton fibers on the seed would quickly disintegrate while generating heat from the reaction of the acid with the moisture in the seed. The residue would be washed away with water. Subsequent to washing, the seed would be required to be neutralized with soda ash, lime or anhydrous ammonia. This method is referred to as the wet acid method. As can be recognized, problems are related to the use of concentrated sulfuric acid since it is extremely corrosive to machinery and dangerous to handle. Further, a large amount of energy is utilized in order to dry the seed. The use of concentrated sulfuric acid also causes soil and water pollution. This has become of increasing concern with various state and federal pollution monitoring and enforcement agencies.
A further chemical delinting process utilized hydrochloric acid to hydrolyze the lint. The advantage of the dry gas or hydrochloric acid system was the elimination of possible ground water pollution. However, the method required the use of a hazardous gas under pressure and was limited to use in a dry climate. The hydrolyzed lint produced by the process is a very fine dust or powder-like consistency and is very difficult to separate in present day air cleaning monitoring systems so as to remove the dust and fumes from the work area before circulating the air outside the plant.
An improved sulfuric acid delinting method was developed using dilute sulfuric acid. This method eliminated the need for a large evaporation pond by recycling the solution not consumed in the process. The dilute acid system required a continuous feed centrifuge which removed water from the dilute acid applied to the seeds so as to concentrate the acid. This chemical process had the disadvantage of using a corrosive acid, was messy, required large amounts of energy to run the centrifuge and to dry the seed. As the centrifuge equipment is extremely expensive and maintenance is very costly, the dilute sulfuric acid system has met with some disfavor. A modification of this process was developed in the early 1980s so as to eliminate the centrifuge and its high cost; however, the modification slows the cleaning process and requires more energy for drying.
Small-scale mechanical delinting systems are also known. Examples of such systems are U.S. Pat. Nos. 396,996; 397,448; 563,647; 645,169; 659,840 and 1,014,518.
U.S. Pat. No. 396,996 is typical of a machine which abrades cottonseed after passing the seed through a cotton gin and a lint removing machine. The object of the disclosure relates to the removal of short lint or fine wool fibers left on the seed after having been cleaned in a gin and linting machine. The short cotton fibers are removed by an abrading action and dropped through slots at the bottom section of the shell of the machine by action of a brush system. The abraded, cleaned seed is delivered at either end.
U.S. Pat. No. 397,448 discloses a machine for delinting cottonseed is again subjected to an abrading surface and therefore, an abrading action. The machine not only removes the cotton lint from the seed, it also strips the seed of the hulls and further damages the seed.
U.S. Pat. No. 563,647 again discloses a cottonseed delinting machine which uses an abrading surface of emery material. A cylindrical outer surface is disclosed as being lined with an abrading material and further abrading material is also provided by an abrading cylinder covered with emery. An inlet opening is provided with a hopper or other pipe through which the seed is fed. Beneath the inlet, an inner cylinder is arranged spirally around its periphery to start the seed toward the opposite end and to push the seed between the abrading surfaces. At the bottom of the outer casing and at the opposite end from the inlet, an outlet is provided for discharging the seed and the lint.
U.S. Pat. No. 645,169 again presents a delinting machine which uses an abrading action for separating the lint from the seed. The perforated abrasive cylinder of the device is coated with emery or other suitable abrasive material. The abrading arrangement is such that abrading blocks 18 are secured to rod 17 and succeeding blocks are offset from one another so as to permit seed and lint to fall between the blocks to the bottom of the receptacle. This arrangement permits the seeds to again be picked up and abraded further by the use of the abrading blocks.
U.S. Pat. No. 659,840 discloses a cottonseed delinter which uses carborundum abrading or grinding wheels mounted in a machine for the delinting of cottonseed. The seed is packed together to such an extent that a grinding action grinds away the lint. Of course, this action damages the seed so as to make the seed unsuitable for planting.
U.S. Pat. No. 1,014,518 discloses a cottonseed delinting machine which again uses a carborundum roller arrangement for abrading the seed. Carborundum rollers are utilized in connection with a main shaft while auxiliary shafts are also provided with an arrangement so that carborundum facings are utilized thereon.